Reproduction in some New Zealand Cymatiidae (Gastropoda:Prosobranchia)

The behaviour during reproduction of four species of New Zealand cymatiids is described revealing a year-long courtship period in Cabestana spengleri. Charonia species, Mayena australasia and Monoplex australasiae have only a brief period of courtship prior to egg laying. The female of all species remains with the egg mass until the embryos hatch. This period may be as long as three months in the case of Mayena australasia. Protection of the egg mass seems to be the reason for this brooding behaviour as development proceeds normally in the absence of the female. Anatomically, the genital system of these mesogastropods is approaching the condition seen in more advanced neogastropods particularly with regard to the female.